In downhole applications, such as perforating, it is often necessary to cut wires to length to make electrical connections. Perforating guns in particular have numerous configurations where wire length varies for each application. Existing wiring connections in these applications often are made using splice-type connectors, which connect wires directly to other wires. Electronics and electrical components such as detonators and electrical switches include attached lead wires, which are used to make the splice connections. Wires are pulled out of the component, such as for example a firing head or connector module, spliced together, and then pushed or fed back into the component while being assembled with other components.